|≈||approximately equal to|
|digits||indicates that digits repeat infinitely (e.g. 8.294 369 corresponds to 8.294 369 369 369 369 …)|
A attobarn (symbol: ab) is a unit of area equal to 10−46 m2.
Square hectometre (International spelling as used by the International Bureau of Weights and Measures) or Square hectometer (American spelling) or hectare, symbol hm2, is the unit of area or surface area.